The present invention generally relates to methods and apparatus for measuring and monitoring electric power, and more particularly to a system including sensor devices for measuring electric current.
Power distribution parameters such as power line current, power line voltage and network load distribution are useful for monitoring the efficiency of a power line distribution system. However, such information has not been available in a satisfactory manner to optimize network management. Consider power line current. The current flowing over a given power line may vary depending on the power needs of customers and the conditions of the power line network. Access to real time measurements of the current flowing through power lines at various portions of a network may allow the utility to more efficiently allocate distribution resources. However, current measurements typically have only been available at transfer substations (i.e., a location where the high voltage power lines couple to medium voltage power lines for regional power distribution) and, in some instances, at the customer's power meter. Accordingly, there is a need for measuring power line current and other parameters at many locations.
One challenge for providing such data includes difficulty in obtaining accurate current measurements. Accordingly, there is a need for a system for gathering and communicating power distribution parameters, such as power line current, power line voltage, power line power factor data, harmonic content, transient load conditions (e.g. cold-load pick-up), fault detection, and other such parameters.
Thus, a need exists for an improved sensor device, method of manufacture and use.